1. Field of the Invention
The invention relates to the field of femoral compression devices and in particular to the pressure pad which is fitted to the adjustable screw of a femoral clamp for the purpose of exerting pressure against a femoral incision in order to staunch blood flow from the puncture site.
2. Description of the Prior Art
A number of medical procedures require the puncture of a blood vessel for purposes of entry of a catheter, guide wire or needle. One such common procedure is cardiac catheterization where the femoral artery in a patient's groin area is punctured to allow passage of a long catheter through the artery into the chambers of the heart. Cardiac catheterization procedure aids in diagnosis of various heart disorders and anomalies.
Following withdrawal of the catheter, pressure must be applied to the groin area at the location of puncture in the artery to allow coagulation to take place to prevent bleeding. Several approaches to apply the necessary pressure have been followed. One approach is for a physician or nurse to manually apply pressure to the side of the puncture for an extended period of time. Another approach is to use a mechanical device to apply the pressure such as shown in Semler, "Artery Clamp," U.S. Pat. No. 3,779,249 (1973). This device, called an artery clamp, includes an upright tubular support mounted on the flat base and an arm mounted on the support in a cantilevered or perpendicular fashion to overlie the base. The arm is mounted so that it is vertically slidable along the end of the support. Mounted on the outer end of the arm is relatively inflexible, disc-shaped pressure pad formed from transparent or translucent plastic.
Before removing the catheter from the patient, the physician or nurse places the base of the clamp under the patient's thigh, and slidably positions the arm so that the pressure pad is directly over the puncture site. As the catheter is withdrawn, the arm is manually moved downward toward the base, typically through a screw adjustment, to cause the pad to compress the artery and to prevent bleeding. After blood coagulation has been established, the arm is unlocked and removed.
Another design for a femoral artery clamp is shown by Freund et al., "Adjustable Compress Apparatus," U.S. Pat. No. 4,742,825 (1988). Freund is similar to Semler in that it includes a base, a support and an arm to which a pad is adjustably positioned. The differences between Freund and Semler, for example, as with many other artery clamp designs is in the connection of these various elements to each other and their adjustability.
Another example of an adjustable pressure tourniquet using a screw adjustment with a pad is shown in Plummer, "Tourniquet," U.S. Pat. No. 1,281,653 (1918) in which a screw adjustment on a flexible belt tourniquet is mounted on its lower end with a ball joint fit into expandable socket of a disc-shaped hard pad.
The number of examples of artery clamps or tourniquets using adjustable means to bring a pad to bear against a puncture site could be multiplied even further. A number of different designs are available in the market and among their various other differences, the exact shape and nature of the fitting between the titration or adjustable screw and the pressure pad varies. As a consequence, it is necessary for medical practitioners to stock separate pads for each different type of arterial clamp which may be used or available in their hospital or clinic. The construction details of the fitting between the titration screw and the pad varies from manufacturer to manufacturer and there is no universal standard.
Therefore, what is needed is some type of design by which the need for inventorying multiple types of pads may be avoided.